Effect of Janus nanoparticles on foam snap off in porous media

Nanoparticles can be adsorbed at the gas-liquid interface to improve the stability of foam. However, homogeneous nanoparticles exhibit low surface activity, and their migration to the gas-liquid interface requires significant energy input. This leads to harsh foaming conditions and severely limits the application of homogeneous nanoparticles in foam stability. A microfluidic visualisation model for the study of Janus nanoparticle complex systems was used to investigate the formation behaviour of trapped bubbles in a single connected pore-throat model. The foam generated in the pore showed reduced quantities, sizes, improved quality, and enhanced stability compared to both surfactant systems and hydrophilic nanoparticle complex systems.